1. Field of the Invention
This invention relates to improved lightweight building blocks, and more particularly, to reinforced foam building blocks which may be used to replace heavy cement building blocks such as those used in the construction of buildings in a wide variety of applications where portability and light-weight are advantageous.
2. Description of the Related Art
Lightweight foam structures have been previously used for a number of ornamental applications. But for military applications and sporting requirements such as temporary camp establishments, there has been a need for providing new and improved building blocks, which may be used as a substitute for the conventional cement building blocks in specific applications where lightweight portability is a significant advantage.
U.S. Pat. No. 4,577,447 to Doran discloses construction blocks made from expanded polystyrene beads. The Doran construction blocks are designed to be used with a concrete footing, and separate steel reinforcement rods and pourable masonry cement. The Doran blocks are seated upon the concrete footing, and over the steel reinforcement rods that extend vertically from the footing. The liquid concrete is poured into the spaces in the Doran blocks to provide support. The disadvantage of the Doran blocks is that they lack support without the use of the separate liquid concrete and reinforcement rods.
U.S. Pat. No. 4,614,071 to Sams et al. discloses a building block having a polyurethane or polystyrene body that is sandwiched between a pair of cement slabs. The building blocks are intended to provide thermal insulation and fire resistance. The disadvantage of the Sams building blocks is that the cement slabs, which provide the needed support for the blocks, also provide added weight, which limits their usefulness for portability.
U.S. Pat. No. 4,731,279 to Isshiki discloses assembly blocks that can be used for tables, stools, gates, arches and the like. The Isshiki blocks are made from a polyolefin resin, and have male and female projections as interconnecting structures. The Isshiki blocks are provided with a central bore so that a separate reinforcing bar, such as a metal bar, can be slid through the blocks. The disadvantage of the Isshiki blocks is their need for the use of a separate reinforcement bar, which limits their usefulness as a fast, lightweight construction material. Additionally, the use of the reinforcement bar that is slid through the central bores provides limited support to the block itself.
U.S. Pat. No. 5,699,640 to Bourgeois discloses wall sections that are made from expanded polystyrene. The wall sections are about four feet in length and include a plurality of cells that each have central cavities therethrough which are filled with separate steel reinforcement bars and concrete. The disadvantage of the Bourgeois wall sections is that they lack support without the use of the separate concrete and reinforcement bars.
U.S. Pat. No. 5,771,654 to Moore et al. discloses a method of construction using molded polymer blocks. The method employs a number of the polymer blocks that have a passage portion, which defines a lattice system for receipt of poured concrete. The block system acts as a form for the concrete but also provides for the aesthetics of the structure. The disadvantage of the Moore construction system that it lacks support without the use of the separately poured concrete.
Accordingly, it is a general object of this invention to provide lightweight building blocks with a novel and efficient construction.
Another object of the invention is to provide improved lightweight building blocks, which each include a plurality of exterior walls constructed of reinforced foam insulation material.
An additional object of the invention is to provide an improved lightweight foam building block, such as, for example, a STYROFOAM® building block with a plurality of external walls joined together by interconnected cross-members.
A still further object of this invention is to provide an improved lightweight building block which includes a plurality of foam or STYROFOAM® sides connected together by a plurality of foam or STYROFOAM® cross-members interconnected thereto by a rigid reinforcing material.